Embedding pins in polymer clay is a great way to add a finding without having to put a hole in your shape. You can sandwich pins between clay layers or stick pins straight down into your thicker clay charms. This article and video will cover the sandwiching-between-layers technique.
The trick to making sure the pin stays in and never pulls out is the end being inserted into clay cannot just be a straight pin. If there isn't anything for the clay to hold onto, the pin will eventually come out of the clay, even if you add superglue or other types of adhesives. It needs to have a loop, a bend, or something that will get 'stuck' in the clay. Headpins work great for this as well!
I use 1-Step Loopers by Beadsmith to create a double-ended looped pin. 1.5 mm is my preferred size. I like to make a pin with a loop on each end. One for staying stuck in the clay, and one for attaching findings to.
To use loopers to make loops:
1. Insert a pin into the looper
2. Squeeze the pliers fully to create a loop
3. The Loopers snip off any excess wire and you'll be left with a perfect loop
To add your looped finding to layered clay shapes:
1. Add a little oven-bake adhesive or liquid clay between the layers to help form a strong bond that will really hold onto the pin. (I also often add super glue to hold the pin in place while I work with it, but it's not necessary.)
2. Sandwich one end of the pin between two pieces of clay and press the layers together gently.
Check out this video to see these techniques in action:
I hope this helps you add pin-findings to your earrings, charms, and other clay creations! Please let me know if you have any questions! I can be reached at Scarlet@theclayimpress.com